tonearm

A tonearm is the part of a turntable that carries the phono cartridge and guides the stylus along the grooves of a vinyl record. It must move with minimal friction and maintain precise geometry to minimize distortion and record wear.

Construction and variants: A tonearm typically consists of a rigid arm or wand, a bearing assembly for smooth pivoting, a headshell for cartridge mounting, a counterweight for balance, a cueing lever to lift and lower the arm, and often an anti-skate control. Most arms are straight or S-shaped; common lengths range from about 8 to 12 inches. The geometry is chosen so that the stylus traces the groove with correct tracking across the record, balancing overhang and effective length.

Geometric considerations: Overhang and effective length determine the tracking angle and alignment. Alignment schemes such as Baerwald, Loefgren, and Stevenson specify how the cartridge is positioned relative to the grooves to optimize tracking accuracy across the disc.

Cartridge and setup: Cartridges are typically moving magnet or moving coil. Installation requires aligning the cartridge with a protractor, balancing the arm with the counterweight, and setting tracking force. Anti-skate is adjusted to compensate for lateral bias, and azimuth and vertical tracking angle (VTA) may be fine-tuned for optimal sound. Many modern arms support detachable headshells and adjustable components.

Maintenance and materials: Tonearms use bearings, dampers, and wiring that require occasional maintenance and clean handling to prevent drag or misalignment. Materials range from aluminum to carbon fiber and other composites, chosen for rigidity, weight, and damping properties.